Panamint Systems Corporation is estimating activity costs associated with producing disk drives, tapes drives, and wire drives. The indirect labor can be traced to four separate activity pools. The budgeted activity cost and activity base data by product are provided below.

	Activity Cost		Activity Base
Procurement	$375,300		Number of purchase orders
Scheduling	228,600		Number of production orders
Materials handling	496,400		Number of moves
Product development	725,800		Number of engineering changes
Production	1,422,800		Machine hours

	Number of Purchase Orders	Number of Production Orders	Number of Moves	Number of Engineering Changes	Machine Hours	Number of Units
Disk drives	4,150	420	1,450	10	1,800	1,500
Tape drives	1,900	225	670	7	8,300	3,500
Wire drives	11,300	900	4,100	20	10,400	2,000

The activity-based cost for each disk drive unit is

a.$392.48

b.$21.63

c.$240.34

d.$909.44